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排序方式: 共有295条查询结果,搜索用时 171 毫秒
1.
Sero- and subtypes of group B meningococci causing invasive infections in Finland in 1976-87 总被引:2,自引:0,他引:2
H K?yhty J Poolman H Abdillahi A Sivonen J Eskola E Tarkka H Peltola 《Scandinavian journal of infectious diseases》1989,21(5):527-535
Neisseria meningitidis group B (MenB) strains isolated from 1976 to 1987 in Finland in 339 patients with invasive infection were sero/subtyped by whole cell enzyme immunoassay using monoclonal antibodies to class 1 and 2/3 outer membrane proteins. 66.7% of the strains could be serotyped (class 2/3) and 70.2% subtyped (class 1). No single phenotype was clearly predominant. The most common serotypes were 4 (18.6%) and 14 (17.4%) and the most common subtypes P1.16 (20.1%) and P1.2 (12.1%). The Norwegian phenotype B:15:P1.16 was seen only rarely (a total of 18 strains). Strains from Northern Finland did not differ from those from Southern Finland: no single phenotype caused the slight increase seen in the incidence of MenB infections in the end of 1970s in the North. 相似文献
2.
Ari Mennander Jari Laurikka Pekka Kuukasj?rvi Matti Tarkka 《European journal of cardio-thoracic surgery》2005,27(1):32-34
OBJECTIVE: To assess the impact of postoperative continuous pleural lavage (PCPL) after thoracotomy for the treatment of stage 2 pleural empyema in relation to postoperative length of stay and morbidity. METHODS: Stage 2 pleural empyema was diagnosed with computer tomography. Conservative treatment including antibiotics and pleural aspiration was introduced. 89 patients treated for stage 2 pleural empyema by thoracotomy, pleural discharge evacuation and irrigation after pleural decortication were identified after unsuccessful conservative treatment for 10 days. Whenever pleural discharge remained opaque after operation, PCPL was administered daily through the cranial chest tube and discharge evacuated through the caudal pleural suction (10-15 mmHg) tube. Risk factors related to pleural pus and patient outcome were sought for. RESULTS: Seventy-seven out of 89 patients (86.5%) had clear empyema discharge immediately after pleural decortication and irrigation. Pleural discharge remained opaque despite surgery in 12 out of 89 patients (13.5%) and PCPL was introduced. Presence of a combination of risk factors for pleural empyema, such as dental caries, alcohol abuse or previous inflammatory reaction, was predictive for persistence of opaque pleural discharge after operation (P<0.05). Need for re-thoracotomies (in 11 cases, P=ns) and postoperative deaths (P<0.05) were related with patients who did not have PCPL. The length of the hospital treatment was 20.1+/-3.1 (days+/-SEM) among patients with PCPL and 19.2+/-1.8 without PCPL before possible re-thoracotomy, respectively (P=ns). CONCLUSIONS: Early postoperative (1 day-11 months) mortality was statistically associated with patients having fibrinopurulent empyema but no PCPL. PCPL is a feasible method to clear pleural pus discharge without prolongation of hospitalization and may be recommended after thoracotomy for patients with fibrinopurulent stage 2 empyema. 相似文献
3.
Three different auditory stimulus paradigms were used to elicit P300 potentials. Normal subjects were tested on the classical rare target stimulus, single-stimulus and omitted-stimulus conditions. Noninvasive identification of the cerebral sources of the event-related potentials (ERPs) was performed using spatio-temporal multiple dipole modeling (BESA software) with individually sized spherical head models. The grand average data of each condition was first independently modeled and these models were used as starting values for modeling each individual subject's data. Models for the rare-stimulus condition and single-stimulus condition both consisted of 6 dipoles. Models for the omitted-stimulus condition consisted of 2 dipoles. The dipole locations of the final individual 6-dipole models for the rare and single-stimulus conditions did not differ significantly from each other or from one previous result obtained from a another group of subjects (Tarkka et al. 1995). Super-imposition of the dipole coordinates on the sterotaxic brain atlas suggests that bilateral deep medial temporal lobe structures are the major contributors to rare and single-stimulus P300s. Because both the wave form morphology and the source model of the P300 elicited by single stimulus were close to those of the rare-stimulus P300 it may be that the underlying neural mechanisms eliciting these P300 potentials are essentially the same. 相似文献
4.
Luis F. H. Basile M.D. Panagiotis G. Simos Ina M. Tarkka Donald G. Brunder Andrew C. Papanicolaou 《Brain topography》1996,9(1):31-37
Summary In this study we attempted to extend our previous results on regional specialization of frontal cortical function in humans, by means of magnetoencephalography (MEG). We used a verbal task and predicted that some part of the left frontal lobe would be active during engagement in that task, since the left hemisphere is known to be implicated in language. We did not require a motor response because in previous experiments we observed bilateral frontal magnetic activity, and we suspected that it was due to the addition of movement-related fields to our recordings. Six right handed subjects (three males and three females) participated in the study. The task consisted in silently counting the number of word pairs that matched with respect to semantic category. Experimental runs were composed by series of 120 trials or word pairs. All six subjects presented dipolar magnetic field distributions on the left fronto-temporal area of the scalp, but not on the right, during different portions of the trial duration. These fields were successfully modeled as equivalent current dipoles (ECDs). The spatial ECD coordinates were translated onto magnetic resonance image (MRI) coordinates for each subject. The dipole positions were typically near the cortical surface corresponding to areas 6 and 44 of Brodmann. No dipole-like sources were observed in the right frontal lobe.This research was supported by grant NS 29540-005A1 from the National Institutes of Health, Washington, D.C. 相似文献
5.
6.
Beneficial effects of ischemic preconditioning on right ventricular function after coronary artery bypass grafting 总被引:6,自引:0,他引:6
Wu ZK Tarkka MR Pehkonen E Kaukinen L Honkonen EL Kaukinen S 《The Annals of thoracic surgery》2000,70(5):1551-1557
BACKGROUND: Preservation of right ventricular myocardium is unsatisfactory in patients with critical stenosis or occlusion of the right coronary artery. The aim of this study was to investigate whether ischemic preconditioning (IP) improved the recovery of right ventricular function after coronary artery bypass grafting. METHODS: Forty patients with three-vessel disease who had coronary artery bypass grafting were randomly assigned to the IP group (n = 20) or control group (n = 20). In the IP group, two cycles of two minutes of ischemia after three minutes of reperfusion were given before cross-clamping. Hemodynamic data were collected. Right ventricular ejection fraction was measured by thermodilution. RESULTS: Right ventricular ejection fraction and right ventricular systolic volume index were decreased post-operatively (lowest value at 6 hours postoperatively). The changes in right ventricular ejection fraction were significantly milder in the IP group postoperatively (p = 0.012). The decrease in right ventricular systolic volume index postoperatively was also less in IP patients (p = 0.002). Fewer inotropic drugs were used in the IP group compared with controls. CONCLUSIONS: Ischemic preconditioning had a myocardial protective effect on recovery of right ventricular contractility in patients who had coronary artery bypass grafting. 相似文献
7.
Mika Kohonen Ossi Teerenhovi Tiina Terho Jari Laurikka Matti Tarkka 《Scandinavian cardiovascular journal : SCJ》2013,47(1):69-71
Objectives. Atherosclerosis is a systemic disease affecting several vessels of the body. Coronary artery patients requiring bypass surgery have increased prevalence of carotid artery atherosclerosis which is known to increase operative risk in coronary artery bypass surgery (CABG). Radial artery is often screened for grafting purposes preoperatively. Our aim was to find out whether atherosclerotic changes in forearm vessels are correlated and could reveal risk to carotid artery disease. Design. Eighty-five patients planned for elective CABG were examined with ultrasonography preoperatively. Biplane ultrasonographic scanning was performed on forearm arteries and both carotid arteries. Results. Eleven patients had pathologic changes in the wall of forearm vessels. Carotid artery disease was found on 19 patients. Forearm vessel pathology was found to have correlation to carotid artery disease. When forearm arteries show atherosclerotic pathology the risk of having carotid disease is at least five-fold, in subgroups even higher. Conclusions. Forearm arterial pathology is correlated to carotid artery disease. When forearm vessel pathology is evident in preoperative examination, scanning of the carotid vessels should be considered. 相似文献
8.
Ushanandini Mohanraj Maija Jokinen Rajita Rayamajhi Thapa Minna Paloniemi Timo Vesikari Maija Lappalainen Eveliina Tarkka Zaiga Nora-Krkle Anda Vilmane Kim Vettenranta Charles Mangani Sami Oikarinen Yue-Mei Fan Per Ashorn Elina Visnen Maria Sderlund-Venermo 《Viruses》2021,13(3)
Three human protoparvoviruses, bufavirus (BuV), tusavirus (TuV) and cutavirus (CuV), have recently been discovered in diarrheal stool. BuV has been associated with diarrhea and CuV with cutaneous T-cell lymphoma, but there are hardly any data for TuV or CuV in stool or respiratory samples. Hence, using qPCR and IgG enzyme immunoassays, we analyzed 1072 stool, 316 respiratory and 445 serum or plasma samples from 1098 patients with and without gastroenteritis (GE) or respiratory-tract infections (RTI) from Finland, Latvia and Malawi. The overall CuV-DNA prevalences in stool samples ranged between 0–6.1% among our six patient cohorts. In Finland, CuV DNA was significantly more prevalent in GE patients above rather than below 60 years of age (5.1% vs 0.2%). CuV DNA was more prevalent in stools among Latvian and Malawian children compared with Finnish children. In 10/11 CuV DNA-positive adults and 4/6 CuV DNA-positive children with GE, no known causal pathogens were detected. Interestingly, for the first time, CuV DNA was observed in two nasopharyngeal aspirates from children with RTI and the rare TuV in diarrheal stools of two adults. Our results provide new insights on the occurrence of human protoparvoviruses in GE and RTI in different countries. 相似文献
9.
S.D. Forssten E. Kolho A. Lauhio L. Lehtola S. Mero A. Oksaharju J. Jalava E. Tarkka M. Vaara J. Vuopio-Varkila 《Clinical microbiology and infection》2010,16(8):1158-1161
The molecular epidemiology of 33 Escherichia coli and 81 Klebsiella pneumoniae extended-spectrum β-lactamase-producing health-care-associated and community-acquired isolates collected in the Helsinki district during 2000–2004 was investigated. Clonality studies, antimicrobial susceptibility and genotyping of the isolates were performed. Newly emerging CTX-M-producing E. coli and blaSHV-12-producing K. pneumoniae isolates were detected. Clonal clusters of both species persisted throughout the study period. 相似文献
10.
The objectives of the study were to discover the main determinants for the prevalence of varicose veins in a general population, and to assess the possibilities for prevention of this common surgical disease. Varicose veins were evaluated in three defined cohorts of 3284 men and 3590 women aged 40, 50, and 60 years by using a validated questionnaire. The response rate was 75% among men and 86% among women, and varicose veins were determined by self-assessment. Increasing age, female sex, childbirths, standing posture at work, higher weight or height, and positive family history were significantly associated with varicose veins in a univariate analysis. These factors were further taken into a multivariate logistic regression analysis, and female gender (adjusted odds ratio, OR 2.2), increasing age (OR 2.2-2.8), a reported positive family history for varicose veins (OR 4.9), increasing number of births (OR 1.2-2.8), standing posture at work (OR 1.6), and higher weight (OR 1.2) and height (OR 1.4) were found to independent and significant risk indicators of varicose veins. Increasing age, positive family history of varicose veins, and child-births in women were the most important factors in terms of population etiologic fractions. Familial predisposition and pregnancy-related factors bear important associations with varicose veins. Thus prevention of varicose veins appears to be difficult. Varicose veins are nonlethal and, therefore, higher age is related to higher prevalence. 相似文献